During my rebuild the caps became mixed (I think). The
stamped numbers on the caps are illegible. I need some
confidence before continuing assembly. There is one large
cap, intake rear, for the Tacho. This is a late model 3.8
XK150 incidentally. There are two C2172’s and 5 C2171’s.
Can someone tell me the correct location for the C2172’s
please.
Thanks
Mike
Washington DC
PS Please do not mention line boring I’m nervous enough
already.–
Britfmdc
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
The C2172's go on the intake and exhaust cam shaft's front bearings.
Regards,
Paul M. Novak
1990 Series III V12 Vanden Plas
1990 XJ-S Classic Collection convertible
1987 XJ6 Vanden Plas
1984 XJ6 Vanden Plas
1969 E-Type FHC
1957 MK VIII Saloon
Ramona, CA
P.M.Novak7@gmail.com-----Original Message-----
From: owner-xk-engine@jag-lovers.org [mailto:owner-xk-engine@jag-lovers.org]
On Behalf Of Britfmdc
Sent: Monday, March 03, 2014 6:31 PM
To: xk-engine@jag-lovers.org
Subject: [xk-engine] Cam bearing caps
During my rebuild the caps became mixed (I think). The stamped numbers on
the caps are illegible. I need some confidence before continuing assembly.
There is one large cap, intake rear, for the Tacho. This is a late model
3.8
XK150 incidentally. There are two C2172’s and 5 C2171’s.
Can someone tell me the correct location for the C2172’s please.
In reply to a message from Britfmdc sent Mon 3 Mar 2014:
Mike,
Put on your detective hat and use a strong light and magnifier
to look for more clues. Look closely at the dowels. Fit the
new bearings and cams without the valves and check for binding
on rotation. Measure or check the clearances with Plastigauge.
There are two cam stud torque specs, 8 and 15 , I always use
the higher spec because you never know what the PO used.
Paul–
The original message included these comments:
During my rebuild the caps became mixed (I think). The
stamped numbers on the caps are illegible. I need some
confidence before continuing assembly. There is one large
cap, intake rear, for the Tacho. This is a late model 3.8
In reply to a message from Britfmdc sent Mon 3 Mar 2014:
Mike,
One further comment. Don’t assume that the caps are all
oriented the same way - i.e. that the part number is the
same way up on each cap. On my XK140 engine some caps were
one way round, and others the other way round. I’m pretty
sure that this was from the factory, as each cap was stamped
with a number that matched up with a corresponding number
stamped on the top of the head, and the position of the
stamps imply different orientation of the caps. Hopefully
with some detailed detective work you will be able to work
out which cap came from where, and which way round it
was…